There is something strange with moving floors and package loss: there are "jumping" floors shown on the client. If loss happens floors move instantly to the height they should move with given speed.
In my opinion it happens too often for just internet lags and bad connections.
Also I think it's not a new problem.

What I tested with 1.10b6:
- map01 and map02 on a LAN server (client and server on different PC's): no Loss in netstats, everything is fine
- map01 on [SDA]: I have Loss and sometimes "jumping" floors (low traffic, good ping) Screenshot
- map02 with 200 tags on [SDA]: Also Loss and jumping floors Screenshot

I don't know if this is exactly the same bug but while going down on a moving floor can result in the floor becoming transparent and the items becoming invisible (as shown in the video in the OP), going up at the same type of moving floor can result in being "sunk" in the floor until the movement stops.